| Clarion Design Services Ltd | Waterlooville | 2000 |
| Clarion Water Limited | Macclesfield | 2013 |
| Clarion Water Services Ltd | London | 2015 |
| Clariqua Ltd | Banbury | 2025 |
| Clarissima Designs Limited | Coventry | 2017 |
| Clarity & CUT Limited | Tadcaster | 2023 |
| Clarity 4 Food Limited | Nottingham | 2014 |
| Clarity Arts Limited | Harrogate | 2011 |
| Clarity Ceramics Limited | Liverpool | 2025 |
| Clarity Collective Ltd | Rickmansworth | 2025 |
| Clarity Computer Systems Limited | Telford | 2019 |
| Clarity Copiers (Western) Limited | Somerset | 1980 |
| Clarity Events Managment MCR Ltd | Manchester | 2024 |
| Clarity Fabrications Ltd | West Bromwich | 2009 |
| Clarity Gazebo Limited | Birmingham | 1969 |
| Clarity Glass Ltd | Manchester | 2018 |
| Clarity Group Limited | Birmingham | 1989 |
| Clarity Marine Ltd | Lymington | 2026 |
| Clarity Office Supplies Limited | Birmingham | 1975 |
| Clarity Optical Limited | Nottingham | 2018 |
| Clarity Plastics Limited | Weston-Super-Mare | 2025 |
| Clarity Print Limited | Birmingham | 1989 |
| Clarity VM Limited | North Ferriby | 2012 |
| Claritycraft Limited | Edenbridge | 2020 |
| Claritystamp Limited | Edenbridge | 2005 |
| Clark & King Limited | Rayleigh | 1962 |
| Clark & SON (Long Melford) Limited | Woodbridge | 2013 |
| Clark & Sutherland Limited | Elgin | 2000 |
| Clark and Evans Limited | | 1944 |
| Clark and Prince Limited | Hemel Hempstead | 2021 |
| Clark Audio Innovation Ltd | Welwyn Garden City | 2021 |
| Clark Clay Industries Limited | Ellesmere Port | 1987 |
| Clark Construction (Scotland) Ltd | Glasgow | 2024 |
| Clark Door Limited | Dumfries | 1969 |
| Clark Electronics Limited | Stirling | 2011 |
| Clark Equestrian Ltd | Guildford | 2018 |
| Clark Fixings Limited | Darlaston Wednesbury | 1978 |
| Clark FM Limited | Barking | 2019 |
| Clark Leavy Pallets Ltd. | Falkirk | 2023 |
| Clark Machinery Services Limited | Gloucester | 2011 |
| Clark Manufacturing Ltd | Falkirk | 2026 |
| Clark Masts Systems Limited | Harrow | 1979 |
| Clark Masts Teksam Limited | Harrow | 1979 |
| Clark Mechanical Services Ltd | Inverurie | 2020 |
| Clark Mezzanines Ltd | Gateshead | 2003 |
| Clark Offshore Services Limited | Blandford Forum | 2015 |
| Clark Playground Installations Limited | Frome | 2014 |
| Clark Quarmby Limited | Elland | 1997 |
| Clark Tracks Limited | Dumfries | 2004 |
| Clark's Bakers (Easingwold) Limited | York | 1985 |
| Clark's Bakery & Coffeehouse Limited | Coventry | 2025 |
| Clark's Boatworks Limited | Weymouth | 2003 |
| Clark's Cycle Systems Limited | Derby | 2004 |
| Clark's Oils Limited | Bishop Auckland | 2024 |
| Clark's Plant Services Ltd | Bristol | 2025 |
| Clark-Drain Limited | Peterborough | 1978 |
| Clarke & Adkins Ltd | Daventry | 2023 |
| Clarke & Barker Fabrications Limited | Stockport | 2025 |
| Clarke & Co Marine Plant Ltd | Skipton | 2023 |
| Clarke & Kelly Tooling Ltd | Chinnor | 2017 |
| Clarke & Strong Limited | Coventry | 1940 |
| Clarke Bros. Limited | Woodhouses, Failsworth | 1978 |
| Clarke Cable Limited | Congleton | 1972 |
| Clarke Chapman Limited | Retford | 2000 |
| Clarke Clothing UK Limited | Nottinghamshire | 2004 |
| Clarke Concrete Services Limited | Walsall | 2022 |
| Clarke Controls & Distribution Limited | Kingswinford | 2003 |
| Clarke Controls Group Limited | Manchester | 2025 |
| Clarke Controls Limited | Manchester | 2003 |
| Clarke Electrical Services Ltd | Northants | 2003 |
| Clarke Elliot Norman Associates Limited | Sherborne | 1988 |
| Clarke Heavey Stonemasonry Ltd | Doncaster | 2024 |
| Clarke Kitchens and Bedrooms Ltd | Congleton | 2018 |
| Clarke Lane Engineering Limited | Tamworth | 1996 |
| Clarke Manufacturing Ltd | Liverpool | 2013 |
| Clarke Meats Limited | Huddersfield | 1999 |
| Clarke Pharma Consulting Limited | Darlington | 2017 |
| Clarke Refrigeration Services Limited | Wakefield | 2008 |
| Clarke Richardson Fabrications Ltd | Poole | 2002 |
| Clarke Signs Scotland Limited | Glasgow | 2001 |
| Clarke Stone Direct Ltd | Belfast | 2025 |
| Clarke Stonemasonry & Restoration Ltd | Doncaster | 2017 |
| Clarke Talbot Renewable Energy Ltd | Corby | 2022 |
| Clarke TIN Whistle Company Limited(The) | Tonbridge | 1986 |
| Clarke Unique Structures Ltd | Stoke-On-Trent | 2023 |
| Clarke Upholstery Limited | Stoke-On-Trent | 2018 |
| Clarke Welding Services Limited | Bury St Edmunds | 2007 |
| Clarke's Bakery Ltd | Sudbury | 2023 |
| Clarke's Engineering Contracting Ltd. | Chesham | 2014 |
| Clarke's Maintenance Ltd | Birmingham | 2018 |
| Clarke's Solutions Limited | Cannock | 2003 |
| Clarke-Rendall Business Furniture Limited | Milton Keynes | 1992 |
| Clarkeprint FM Limited | | 2004 |
| Clarkeprint Limited | West Midlands | 2000 |
| Clarkes Carpentry Limited | Milton Keynes | 2016 |
| Clarkes Commercial Repairs Limited | Ebbw Vale | 2025 |
| Clarkes Crankshaft Limited | Halesowen | 1990 |
| Clarkes Farm Organics Ltd | Carmarthen | 2023 |
| Clarkes Personalised Products Limited | London | 2022 |
| Clarkes Safety Mirrors Limited | Telford | 2006 |